The whole world is looking for the energy that it considers the driving forces for any development in the world. On the other hand, it re sorted to energy inherent in petroleum and the world felt that this energy will wind up. For this reason, the developed countries directed their research to reduce the fuel consumption of the vehicles in addition to using the renewable energy. This paper p roposes a new expert system for optimizing the tyre drawbar pull, especially for off road vehicles. The system depends on measuring the wheel slip to control on the tyre inflation pressure by using the self-inflation pressure system to maximize the drawbar pull for the off road vehicles and accordingly to reduce the fuel consumption.